Slide-rule.



H. W. TOMLNSON.

SLIDE RULE.

AFPLIOATION FILED APRS, i913. l 1 08,480Q Patented Augi 25, 1914 ,nluuurlrdllllalalalvalffrf is adaptable for receiving the various UNITED sras rarer. onine HENRY WEBSTER TOlVILINSGN, DE CHICAGU, ELLNGIS.

SLDE-RULE.

Specification of Letters atent.

atented Aue'. 25, 1914.

To all whom 'it may concern Be it known that I, HENRY lNnns'rnn ToMLiNsoN, a citizen 'of the United States, residing at Chicago, in the county of Cool; and State oi' Illinois, have invented a new and useful lmprovement in Slide-Rules, ci' which the following is a specification.

My invention relates tocertain new and useful improvements in slide-.rules,and is iullydescribed and eXpla-ined'in the specifi cation and shown 4in the accompanying drawings, in which Figure 1 is an elevation otjmy improved slide-rule; Fig. 2 is a section on the line E2 of Fig. 1;- Fig. 8 is a section on the line al oi Fig. 41, but with the slides removed; Fig. l is a transverse section through the two slides, and Fig. 5 is a section on the broken line 5 of Figul, showing the means for lock-- ing one slide and the construction of the runner.

The present slide-rule is adapted in its construction to receive upon its various members any sort of mathematical markings which may be desired to enable it to accomplish the particular type of calculation or calculations for which it may be designed. The novelty here sought to be covered, however, inheres entirely in the mechanical construction and not in any n'lathematical arrangement of the figures which will be applied to the members of' the rule, and I' therefore have not shown any markings whatever upon thevarious members, it being understood that they may be marked as desired. It may be added that am engaged in manufacturing the rule ot the lVinslow Patent No. 766,009, granted July 26th, 1904, and that the present rfille gures shown therein, either in the identical roi-1n therein illustrated, or with 'certain trifling modilications, which have been adopted for convenience. The primary aim of the. present construction is to afford a slide-rule adaptable for receiving the tigures of this particular Winslow rule, o r any other slide-rule, which rule shall be very compact and of astrong and indestructible character. j

Referring to the drawings, 6 and7 are the two surface plates or members of the frame ot the slide-rule, these members constituting xed sale-receiving members. These surface-members are formed from sheetmetal or any other suitable,material of the size. ot the complete sliderule, and a central perforation or opening is cut through said two surface-members'leaving the lateral portions oit each connected by bridges 8 at the end. These bridges S are bent in opposite directions from the plane ot the s urface-members, as is clearly shown in Fig. 3, to afford between them clearance ttor the slides, which are or the same thickness as the frame. The surface-members or' the frame are spaced apart by spreaders or intermediate plates 9 and 10 on the two sides, each oi said spreaders being ot sheetanetal. rlhe frame thus consists'entirely of sheetmetal, and it is of the thickness ci three sheets ot metal used, except at the ends, where the bridges are bent apart, an additional thickness of the metal each,l whereby there is provided between them a clearance i'or a slide three sheets oi metal thick.

In the form of construction illustrated, two slides are used, the construction .ot which is shown in Fig. (lne ot the slides consists of three thicknesses ot metal, 11, 12 and 1B; the intermediate piece 19. being ci' greater width than the-two surface pieces 1l and 13 and projecting therefrom on the two sides to iform tongues. The other slide likewise consists of three sheets or metal, 14 1,5 and 1G, the intermediate member 15 being oii'sct with reference to. thc two surface members so as to. form a projecting tongue on one side and a groove on the other; side adapted to receive the tongue 'formed by the projection ofthe member 12 on the adjacent slide. The spreadersl and l'O in the frame fall suliicicntly short of the edges or' the opening punched therethrough that the projecting tongues on the two slides can enter the groove thus formed, all. as shown in the drawings.

ln making calculations, it is frequently desirable to render one factor permanent i'or constant use through a long series` of calculations. 'In calculating the strength of beams for example, for which the 'Winslow slide-rule is particularly designed, va given fiber stress is assumed, so as to afford a proper margin or safety for the entire structure and, when this factor is once determined, it may remain constant throughout all the calculations of all the pieces of the building. In thisnnd 'similar cases, itis desirable to lock one of theslides in a rela tively-.tired purpose the locking nieans shown in Figs. l and 5, is provided. be seen in these figures that the member 9 is cut away at a central point., so to render the two surface members of the traine yielding at that point, and through this yielding` part is passedv a screw vl? upon lwhich is a nut 18. lli/.7 hen this nut is tightened up, the surfaceinenibers oi the traine will he sprung t-A gether tightly to clasp the tongue of the ad- `acent slide, locking it in a relatively-lined position. For the purpose of reaching across the broad side of the frame upon whiciuin practice, it is sometimes desirable to placs'a .series of scales or a large number oi iiigures, a runner is provided, consisting a lll-shaped sheet-metal piece bent over the 'ci the slide-rule, having openings in it.; rtwo or ends in which are'placeol transparent windows, of Celluloid or the lilie, 50, upon which windows may be drawn lines z' t rightangles to the sides of the sliderule wlierebv to get the usual function of a runner. it will thus be seen that in a peculiru'l)r simple, compact and durable forni, l have provided a slide-i'ule capable of receiving arithmetic or logarithmic markings whereby to fit it for a large number of calculatir' purposes. rlhe slide-rule, which lt have bt`J for the markings in accordance with 'the uforegoing design, is only one-siXl teenth of an inch thick, except at the ends, where the bridges make it an eighth of an inch thick. Furthermore, the mechanical. construction is such that both surfaces of the rule are practicall;7 alike and both 'faces can be used in accordance with common practice, if desired. Stilliiurther, the de; sign is such that when oncel dies are made `lor the manuil:u'ture ot the structure from rl notai, manufacturing; liccornes quite and cheap, and it will thus be' pos sible, .in .cordaine with this design, to maxe slide-rulesI in. vaiiious forms and at very low p ioes, particulzuljv when they are supplied with scales of the types for which there a demand.

ll/vhile in the di' wings have illustrated a. structure hziiving a traine with two slides,

it will be nuuiiest that. :tar ascertain tea-Y tures oi the invention are concerned, either more or le f' slides could he used and the proi'iortions in dimensions can be varied as desired to suit the arithnietical demands or the o rticular rule. 'l'l'iereore while l. haver( scribed the present in detail, l

i et

do not intend to he limited thereto, except as pointed out in the following claims in which it is inyintention to set forth all the novelt;Y inherent vin the construction as position and to accomplish this fhroadiy incenso the art.

What ll claim as new and desire to secure by Letters Patent is l. l slide -rule, comprising a frame `formed with an opening, the side walls of which are formed with grooves and the end walls are formed withv transverse openings, two adjacent sl'idalole members, each consistingo two surface' plates and an inter mediate plate, the edges of the intermediate plate of one member projecting beyond the surface plates to orin tongues, one of the latter sliding-jin one of thei'side ygrooves in the frame, the-surface plates ofthe companion member extending vover one `edge of intermediate plate to :tornil'av roove which reicives the tongue on 'the a jacent slidablo ineinber, the opposite edge ofthe afores-:aid intermediate plate of the corn-A panion member projecting beyond said surface plates to form a tongue which slides in vone of the side grooves in the frame, and clamping means acting at a right angle to the surface of the slidable members.

2. A. slide rule comprising a frame formed oit upper and lower plates provided with elongated registering openings and two side intermediate plates parallel with the side walls of the openings, the' ends of the upper and lower plates of the frame between the inner edges of tlie'two intermediate side plates beingspaced to form passages for a slidable member, one of the intermediate side plates being cut away, two adjacent 4slidable membersj each consisting of two surface platesl and anintermediate plate, the edges of the intermediate' plate of one member projecting' beyond the surface plates to form tongues, one of the latter sliding' iu one oit the side grooves in the traine, the surface plates of the companion member extending' over one edge of its intermediate plate to form a groove which receives the tongue on the adjacent slidablemember, the opposite edge of the aforesaid intermediate plate'of the companion member projecting` bevond said surface plates to forni a tongue which slides in one of the side lgrooves in the frame. and means adjacent the cut awayv portion of the side intermediate plate for drawing the upper and lower plates of the 'trame together to bind the tongue of the adjacent slidahle member.

ln testimony whereof l have hereunto set in v hand th is 14th dav of January, 1913.

HENRY' WEBSTER TllllilllSON.

lu presence ot' two subscribing witnesses:

.Yuma B. DEinBoRN, A, C. FISCHER.-

as is Aperi'nitted by the state of -1 

